Some of my questions were already asked in your OT post about power, which I hadn't read, sorry.

Another option for the power would be to replace the socket on the back with a switched, fused, filtered model. All in one unit. What do you do with the switch on the front? just switch the DC. Much safer. You don't have to worry about switching high voltages and it's a direct connection between the socket and the power adapter inside.

I really think you should have the ground connected to the chassis, irrespective of how your apartment is wired. You might move one day.